模具-浇口.pdf

Chapter 7 MOLD DESIGN continued Sprue Bushing Figure 7-18 parting line. Though they can be cut directly into the mold, sprue bushings 0.5-in or 0.75-in Spherical Radius are usually purchased as off-the-shelf Locating Ring items and inserted into the mold (see 0.5-in/ft Taper figure 7-18). The head end of the sprue bushing comes premachined with a spherical recess — typically 0.5- or Nozzle Tip 0.75-inch radius — to receive and seal 0.02 – 0.08-in Radius off against the rounded tip of the press injection nozzle. The sprue bushing flow-channel diameter typically tapers larger toward the parting line at a rate of